the ac replacement valve seems to be leaking i was wondering what is the average cost of having it replaced..
The ac replacement valve? Well, what you can do is to get the new ac to replace the old ac.
The valve itself is only a couple dollars. Some shops have a tool that will let them replace a valve without dumping the charge but since its likely low you will likely also have to pay the regular AC service fee which is usually $50-100 plus parts and refrigerant.